Tampa Prep 2009-2010 Impact Defense File
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- Ext 1 – Resilient
- Still resilient – deep ocean gene pools
B. WarmingGreenwire in ‘8 (9-30, “OCEANS: Spreading 'dead zones' pushing marine life to brink of collapse – study”, 10:9, L/N)Oceanic "dead zones," water columns with so little oxygen that they are hostile to aquatic life, are growing worldwide, pushing coastal marine populations closer to collapse than previously understood, according to a study released yesterday. Many of the zones are caused by dying algae blooms, the product of excessive nutrients in the water often from fertilizer runoff, while others are products of shifting water conditions tentatively linked to climate change. Dead zones are growing globally at a rate of 5 percent per year and are "emerging as a major threat to coastal ecosystems globally," scientists from the Mediterranean Institute for Advanced Studies in Spain reported in a report published in the journal Proceedings of the National Academy of Sciences. Ext #1 – ResilientOceans resilient – tons of variety in speciesThe Economist in ‘6 (“The conundrums of the deep dark sea; Marine conservation”, 12-16, L/N)The ocean contains even stranger and more resilient creatures than anyone imagined—but humans cannot agree on how to conserve them FRIGID, lightless waters, many fathoms below the ice of Antarctica and far from any open sea, might not sound like an ideal home—but there are scores of species, including jellyfish and crustaceans, who find that it suits them perfectly well. Where and how this newly discovered aquatic community gets enough food to sustain itself in such a dark, icy world remains a mystery. For militants in the cause of marine ecology, the latest revelations by the Census of Marine Life—a private initiative to probe the oceans of the world, at a cost of up to $1 billion—provide one more argument for reeling in the world's fishing fleets, and for denouncing governments that obstruct conservation agreements. Viewed one way, the census report might perhaps be read as evidence that life-forms are even more robust, and capable of adapting to extraordinary variations in the environment, than people suspected. For example, deep in the equatorial Atlantic the survey found fluids spewing from the Earth's interior at a temperature high enough to melt lead—and shrimps, mussels and clams which somehow took the heat. Other finds included furry crustaceans (pictured above) and lobsters as long as a man's arm. Still resilient – deep ocean gene poolsIPS in ‘6 (Interpress Service, Sephen Leahy, “ENVIRONMENT: DEEP OCEANS TEEMING WITH EXOTIC MICROBES”, 7-31, L/N)The world's oceans may contain 100 times more types of microbes than previously believed, scientists revealed Monday. A single liter of sea water drawn from the deep ocean contained more than 20,000 different types of bacteria, when just 1,000 to 3,000 were expected. This wealth of marine microbial diversity has major implications regarding the role of marine bacteria and the evolution of the oceans, report a group of international scientists in a paper published in the United States by the July 31 edition of the Proceedings of the National Academy of Sciences journal. "Microbiologists have formally described 5,000 microbial 'species,' " says Mitchell Sogin, director of the Marine Biological Laboratory's (MBL) Josephine Bay Paul Center for Comparative and Molecular Biology and Evolution, located in Woods Hole, Mass. "This study shows we have barely scratched the surface," Sogin said in a statement. Water samples were taken at depths of 550 to 4,100 meters at eight Atlantic Ocean sites between Greenland and Ireland, as well as Pacific sites that included a hydrothermal vent on an underwater volcano 480 kilometers off the coast of Oregon. The vast majority of microbes are previously unknown, low-abundance organisms theorized to play an important role in the marine environment, Sogin said. Although not widely recognized, microbes have shaped life here on Earth, says Julie Huber, Sogin's colleague at the MBL. They play important roles in the global carbon and nitrogen cycles both in the oceans and on the surface of the planet, Sogin told IPS. "The marine microbial biosphere is the largest habitat on Earth, and the sub-seafloor is the least explored part," she said. More is known about the surface of Mars than the deep oceans, in large part because it is so difficult to "see" what is going on at the bottom of the ocean, most of which lies in utter darkness under the enormous pressures of 2,000 or more meters of water. This new discovery of microbial abundance required the use of a Canadian deep sea underwater robot vehicle called ROPOS that can dive to 6,000 meters to obtain samples around an active underwater volcano in the Pacific. In the Atlantic, a team lead by researchers from the Netherlands used an ingenious system of bottles that opened and closed at precise depths, Huber said. The main technical breakthrough, however, involved using a revolutionary new DNA technique, called "454 tag sequencing," that requires only small snippets of genetic code to identify an organism. "Peering through a laboratory microscope into a drop of seawater is like looking at the stars on a clear night," says marine microbiologist Victor Gallardo of Chile, vice chair of the Census of Marine Life. This study is part of the International Census of Marine Microbes (ICoMM), a project of the Census of Marine Life, a 10-year global initiative started in the year 2000 that now involves more than 1,700 researchers in 70-plus countries in efforts to assess and explain the diversity, distribution and abundance of life in the oceans -- past, present, and future. "The '454 tag sequencing' strategy increases resolution like the Hubble Telescope. We can see marine microbial diversity to which we were blind before. These rare, ancient organisms are likely to prove a key part of nature's history and strategy," said Gallardo in a statement. To place the challenges of studying deep sea life in context, it was only last week that researchers announced in the science journal Nature the first cultivation of a bacteria from deep-sea hydrothermal vents in the lab, even though such vents were discovered more than 25 years ago. That is mainly because such bacteria grow under unique conditions where waters are very acidic or even poisonous, and temperatures are 100 degrees Celsius or more. And this expedition found tiny creatures that were stranger still. "We found some very unusual DNA that was different from anything ever seen before," said Huber. There were small numbers of very ancient bacteria from millions of years ago that may exist nowhere else now and could be useful in understanding how life in the oceans evolved. "They (the microbes) were the only kinds of life on Earth for approximately 80 percent of the planet's history," said Sogin. These very old microorganisms have survived a great deal of change and may have something to teach as the planet experiences global climate change, he said. "Exploration of this newly discovered 'rare biosphere' could become a major field of marine biology," the scientist added. Another mysterious finding was thousands of different types of bacteria that were only present in small numbers. "This may mean at one time, conditions in the deep ocean were very, very different," Huber speculates. Or perhaps, despite their low numbers, they play an important function such as producing some essential compound. Another hypothesis is that these are a kind of genetic backup system so that if species are wiped out elsewhere, the deep-ocean remnants could re-populate those areas. "That could make the oceans more genetically resilient," she said. Directory: files -> documents documents -> North Mankato Taylor Library documents -> In the Red and Brown Water documents -> - documents -> I. Disaster Summary Sheet II. 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